Rapid Response and Critical Repair of Washed-out Highway, Saskatchewan
Areas in southeast Saskatchewan, Canada, received up to 200 millimeters (8 inches) of rain during a 5-day period in the summer of 2014. During the flood event, 1 million cubic meters (more than 264 million gallons) of water was rapidly released when the 14-meter-high (45-foot-high) embankment where Highway 22 crosses Pearl Creek was breached, washing away a portion of the roadway.
In July 2014, the Saskatchewan Ministry of Highways and Infrastructure commissioned Tetra Tech to provide emergency response, engineering design, and tender and construction supervision to repair the washed-out section of highway. In a span of just over 6 weeks, Tetra Tech assessed the hydrology of the area and completed a hydraulic and grading design to reconstruct a major hydraulic structure and embankment; obtained permits from regulatory agencies; acquired right-of-way and borrow materials; prepared tender documents; and provided construction administration to rebuild the section of Highway 22 at Pearl Creek.
Tetra Tech provided emergency response services that included arranging for site security, removing and salvaging guardrails, flattening slopes, and constructing a safety barrier across the highways.
We completed a hydraulic design to replace a 3-meter-diameter (9.8-foot) culvert with a 4.9 meter (16 foot) multiplate structure, grading and surfacing design to reconstruct the highway, and erosion control design for the site. We also obtained environmental permits and created tender bid documents for the culvert and highway embankment and surfacing structure.